I was personally convinced that it was a robot programmed with some funny lines, but then I started thinking about how when he was paintballing, he was not in the rec room. If Handibot was just, well, a bot, and not a dude with a microphone, he would probably be present in every section of the game to "help" people out.
Also the supposed voice recognition worked in the favor of comedy too often. And he played paintball pretty well. That was some proper paintball AI for a developer making a game for free.
I don't know what to believe in anymore???? Help me Giant Bomb!